During surgical procedures it is desirable to provide means for collecting the patient's blood from the surgical site, collecting the blood in a bag and reinfusing the patient with his own blood upon completion of the operation. There have been numerous developments recently in the field of autotransfusion devices wherein bags are provided with an inlet tube to draw the blood from the surgical site and deposit it within the bag together with suction means for creating suction within the bag to draw the blood from the surgical site into the bag. In order to provide suction within the bag, it is necessary that the bag be maintained in an open position. However, when the blood in the filled bag is to be reinfused into the patient, it is necessary that the bag be collapsible so as to prevent air from entering the bag.
There have been a number of patents directed to providing autotransfusion bags having means for maintaining the bag in an open position and permitting the bag to collapse when the blood within the bag is to be reinfused into the patient. The Hauer U.S. Pat. No. 4,443,220 provides a flexible bag which is maintained in an open position by means of an external supporting frame which engages pockets on the external face of the bag. When the bag is to be emptied, it is simply removed from the frame so as to permit the bag to collapse.
The Sherlock U.S. Pat. No. 4,838,872 also discloses an autotransfusion device including semi-rigid side walls which are flexibly interconnected including a rigid external cylinder which retains the side edges of the semi-rigid side walls of the bag in a compressed position so as to force the side walls outwardly to a substantially cylindrical shape. Thus, the bag is held in an open position by an external rigid cylinder and when the bag is to be emptied, the external cylinder is removed to permit the bag to collapse.
A further type of reinfusion apparatus is shown in the Gunter U.S. Pat. No. 4,642,088 in which an accordion-like bag structure is provided which is held in an expanded condition by means of spring members attached to the end walls which draw the accordion-like bag structure outwardly.
While devices such as discussed hereinbefore have been effective in maintaining an autotransfusion bag in an expanded position while blood is being drawn into the bag and permitting the bag to collapse when blood is to be withdrawn from the bag, such prior devices are relatively complex and expensive to manufacture. The present invention provides a simplified structure which meets all of the requirements of an autotransfusion device with relatively few inexpensive parts.